# Nexus OS Fails to Send Syslog Records to a Silent Host

DevFeed: [Nexus OS Fails to Send Syslog Records to a Silent Host](<https://devfeed.tech/articles/nexus-os-fails-to-send-syslog-records-to-a-silent-host-102657.md>)

Original publisher: [Read original article](<https://blog.ipspace.net/2026/10/nexus-os-logging-silent-host/>)

Published: 2026-10-27T10:02:00Z

Content type: article

Language: en

Sources: [ipSpace](<https://devfeed.tech/sources/ipspace-net-blog-2.md>)

Topics: [Logging](<https://devfeed.tech/topics/logging.md>), [Network Configuration](<https://devfeed.tech/topics/network-configuration.md>)

Tags: [arp](<https://devfeed.tech/tags/arp.md>), [cache](<https://devfeed.tech/tags/cache.md>), [capture](<https://devfeed.tech/tags/capture.md>), [cisco](<https://devfeed.tech/tags/cisco.md>), [cisco-nexus](<https://devfeed.tech/tags/cisco-nexus.md>), [command](<https://devfeed.tech/tags/command.md>), [container](<https://devfeed.tech/tags/container.md>), [functionality](<https://devfeed.tech/tags/functionality.md>), [integration](<https://devfeed.tech/tags/integration.md>), [messages](<https://devfeed.tech/tags/messages.md>), [netlab](<https://devfeed.tech/tags/netlab.md>), [nexus](<https://devfeed.tech/tags/nexus.md>), [os](<https://devfeed.tech/tags/os.md>), [running](<https://devfeed.tech/tags/running.md>), [send](<https://devfeed.tech/tags/send.md>), [setup](<https://devfeed.tech/tags/setup.md>), [syslog](<https://devfeed.tech/tags/syslog.md>), [tests](<https://devfeed.tech/tags/tests.md>), [version](<https://devfeed.tech/tags/version.md>), [vm](<https://devfeed.tech/tags/vm.md>)

## AI overview

In a test with Cisco Nexus OS 10.6(2), syslog messages to a directly connected host were not sent while the switch's ARP cache was empty, even though the route and syslog configuration appeared valid. Pinging the host populated ARP, but the capture showed only ARP and ICMP traffic. After another configuration action generated a log entry, Nexus sent two buffered UDP syslog records; their timestamps show the first had been generated about nine minutes earlier. The observed behavior suggests Nexus buffers unsent messages but does not initiate the ARP resolution needed to deliver them to a silent host. The excerpt does not establish whether this occurs in other versions or setups.

## Source excerpt

Here's another you can't make this up SNAFU observation I made when running integration tests for netlab Syslog functionality: Cisco Nexus OS cannot send Syslog messages to a directly connected silent host. The setup is as trivial as it can get: a Cisco Nexus OS VM (running version 10.6(2)) connected to a dnsmasq container running rsyslogd. Read more ...